title: Determination of acetolactate synthase activity and protein content of oilseed rape (Brassica napus L.) leaves using visible/near-infrared spectroscopy.
abstract: A new acetolactate synthase (ALS)-inhibiting herbicide, propyl 4-(2-(4,6-dimethoxypyrimidin-2-yloxy)benzylamino)benzoate (ZJ0273), was applied to oilseed rape (Brassica napus L.) leaves in different leaf positions. Visible/near-infrared (Vis/NIR) spectroscopy was investigated for fast and non-destructive determination of ALS activity and protein content in rapeseed leaves. Partial least squares (PLS) analysis was the calibration method with comparison of different spectral preprocessing by Savitzky-Golay (SG) smoothing, standard normal variate (SNV), first and second derivative. The best PLS models were obtained by first-derivative spectra for ALS, whereas original spectra for soluble, non-soluble and total protein contents. Simultaneously, certain latent variables (LVs) were used as the inputs of back-propagation neural network (BPNN) and least squares-support vector machine (LS-SVM) models. All LS-SVM models outperformed PLS models and BPNN models. The correlation coefficient (r), root mean square error of prediction (RMSEP) and bias in validation set by LS-SVM were 0.998, 0.715 and 0.079 for ALS, 0.999, 33.084 and 1.178 for soluble protein, 0.997, 42.773 and 6.244 for non-soluble protein, 0.999, 59.562 and 7.437 for total protein, respectively. The results indicated that Vis/NIR spectroscopy combined with LS-SVM could be successfully applied for the determination of ALS activity and protein content of rapeseed leaves. The results would be helpful for further on field analysis of using Vis/NIR spectroscopy to monitor the growing status and physiological properties of oilseed rape.
authors.affiliation: College of Biosystems Engineering and Food Science, Zhejiang University, Hangzhou 310029, China.
authors.forename: Fei
authors.initials: F
authors.lastname: Liu
authors.forename: Fan
authors.initials: F
authors.lastname: Zhang
authors.forename: Zonglai
authors.initials: Z
authors.lastname: Jin
authors.forename: Yong
authors.initials: Y
authors.lastname: He
authors.forename: Hui
authors.initials: H
authors.lastname: Fang
authors.forename: Qingfu
authors.initials: Q
authors.lastname: Ye
authors.forename: Weijun
authors.initials: W
authors.lastname: Zhou
mesh_terms: D000095:Acetolactate Synthase / Q000378:metabolism*; D000704:Analysis of Variance; D001185:Artificial Intelligence; D029688:Brassica napus / Q000737:chemistry* / Q000201:enzymology*; D002138:Calibration; D005240:Feasibility Studies; D016018:Least-Squares Analysis; D016571:Neural Networks, Computer; D018515:Plant Leaves / Q000737:chemistry* / Q000201:enzymology*; D010940:Plant Proteins / Q000032:analysis* / Q000737:chemistry; D012995:Solubility; D013055:Spectrophotometry, Infrared
chemical_list: D010940:Plant Proteins; D000095:Acetolactate Synthase